System and method for defining and using different levels of ground truth

ABSTRACT

A method, computer program product, and computer system, for receiving a first set of ground truth instances from a first source. A second set of ground truth instances may be received from a second source. The first and second sets of ground truth instances may be weighed differently based on a level of trust associated with each of the first and second sources. The weighted first and second sets of ground truth instances may be applied in a machine learning task executed by a computer.

RELATED APPLICATIONS

The subject application is a continuation application of U.S. patentapplication with Ser. No. 14/825,423, filed on Aug. 13, 2015, the entirecontent of which is herein incorporated by reference.

BACKGROUND

Some traditional QA systems may engage Subject Matter Experts (SMEs) tocreate the ground truth (candidate QA pairs) as part of QA systemtraining. In some QA systems, the collection of this ground truth may bedifficult and time consuming. For example, the process for this may havea unique set of questions that are given to each SME to create this set.In other example systems, a collaborative model may be used where eachSME is given the same questions and then through a group decision (e.g.,voting) come up with the most popular answers that are used to createthe set. Thus, the collection of this ground truth may be one of thelarger costs and efforts put forth when adapting to a new domain orcustomer.

BRIEF SUMMARY OF DISCLOSURE

In one example implementation, a method, performed by one or morecomputing devices, may include but is not limited to receiving, by acomputing device, a first set of ground truth instances from a firstsource. A second set of ground truth instances may be received from asecond source. The first and second sets of ground truth instances maybe weighted differently based on a level of trust associated with eachof the first and second sources. The weighted first and second sets ofground truth instances may be applied in a machine learning taskexecuted by a computer.

One or more of the following example features may be included. Applyingthe weighted first and second sets of ground truth instances in amachine learning task may include adjusting a loss function for at leastone of the first and second sets of ground truth instances based upon,at least in part, the level of trust associated with each of the firstand second sources. Applying the weighted first and second sets ofground truth instances in the machine learning task may include at leastone of a mean-squared error and duplication of instances for the firstset of ground truth instances more than the second set of ground truthinstances. A third set of ground truth instances may be received from athird source. The third set of ground truth instances may be weighteddifferently than the first and second sets of ground truth instancesbased on a level of trust associated with each of the first, second, andthird sources, wherein the weighted first, second, and third sets ofground truth instances may be applied in the machine learning task. Thelevel of trust associated with the first set of ground truth instancesmay be indicative of validation of the first set of ground truthinstances by a subject matter expert. The level of trust associated withthe second set of ground truth instances may be indicative of validationof the second set of ground truth instances by QA system developer, andwherein the level of trust associated with the third set of ground truthinstances may be indicative of validation of the third set of groundtruth instances by a threshold number of crowdsource users. An answer inthe second set of ground truth instances may be updated for associationwith the first set of ground truth instances in response to receivingvalidation of the answer from a subject matter expert.

In another example implementation, a computing system includes aprocessor and a memory configured to perform operations that may includebut are not limited to, receiving a first set of ground truth instancesfrom a first source. A second set of ground truth instances may bereceived from a second source. The first and second sets of ground truthinstances may be weighted differently based on a level of trustassociated with each of the first and second sources. The weighted firstand second sets of ground truth instances may be applied in a machinelearning task executed by a computer.

One or more of the following example features may be included. Applyingthe weighted first and second sets of ground truth instances in amachine learning task may include adjusting a loss function for at leastone of the first and second sets of ground truth instances based upon,at least in part, the level of trust associated with each of the firstand second sources. Applying the weighted first and second sets ofground truth instances in the machine learning task may include at leastone of a mean-squared error and duplication of instances for the firstset of ground truth instances more than the second set of ground truthinstances. A third set of ground truth instances may be received from athird source. The third set of ground truth instances may be weighteddifferently than the first and second sets of ground truth instancesbased on a level of trust associated with each of the first, second, andthird sources, wherein the weighted first, second, and third sets ofground truth instances may be applied in the machine learning task. Thelevel of trust associated with the first set of ground truth instancesmay be indicative of validation of the first set of ground truthinstances by a subject matter expert. The level of trust associated withthe second set of ground truth instances may be indicative of validationof the second set of ground truth instances by QA system developer, andwherein the level of trust associated with the third set of ground truthinstances may be indicative of validation of the third set of groundtruth instances by a threshold number of crowdsource users. An answer inthe second set of ground truth instances may be updated for associationwith the first set of ground truth instances in response to receivingvalidation of the answer from a subject matter expert.

In another example implementation, a computer program product resides ona computer readable storage medium that has a plurality of instructionsstored on it. When executed by a processor, the instructions cause theprocessor to perform operations that may include but are not limited to,receiving a first set of ground truth instances from a first source. Asecond set of ground truth instances may be received from a secondsource. The first and second sets of ground truth instances may beweighted differently based on a level of trust associated with each ofthe first and second sources. The weighted first and second sets ofground truth instances may be applied in a machine learning taskexecuted by a computer.

One or more of the following example features may be included. Applyingthe weighted first and second sets of ground truth instances in amachine learning task may include adjusting a loss function for at leastone of the first and second sets of ground truth instances based upon,at least in part, the level of trust associated with each of the firstand second sources. Applying the weighted first and second sets ofground truth instances in the machine learning task may include at leastone of a mean-squared error and duplication of instances for the firstset of ground truth instances more than the second set of ground truthinstances. A third set of ground truth instances may be received from athird source. The third set of ground truth instances may be weighteddifferently than the first and second sets of ground truth instancesbased on a level of trust associated with each of the first, second, andthird sources, wherein the weighted first, second, and third sets ofground truth instances may be applied in the machine learning task. Thelevel of trust associated with the first set of ground truth instancesmay be indicative of validation of the first set of ground truthinstances by a subject matter expert. The level of trust associated withthe second set of ground truth instances may be indicative of validationof the second set of ground truth instances by QA system developer, andwherein the level of trust associated with the third set of ground truthinstances may be indicative of validation of the third set of groundtruth instances by a threshold number of crowdsource users. An answer inthe second set of ground truth instances may be updated for associationwith the first set of ground truth instances in response to receivingvalidation of the answer from a subject matter expert.

The details of one or more example implementations are set forth in theaccompanying drawings and the description below. Other possible examplefeatures and/or possible example advantages will become apparent fromthe description, the drawings, and the claims. Some implementations maynot have those possible example features and/or possible exampleadvantages, and such possible example features and/or possible exampleadvantages may not necessarily be required of some implementations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an example diagrammatic view of a response process coupled toa distributed computing network according to one or more exampleimplementations of the disclosure;

FIG. 2 is an example diagrammatic view of a client electronic device ofFIG. 1 according to one or more example implementations of thedisclosure;

FIG. 3 is an example flowchart of the response process of FIG. 1according to one or more example implementations of the disclosure;

FIG. 4 is an example feedback loop for updating QA pair answers by theresponse process of FIG. 1 according to one or more exampleimplementations of the disclosure;

FIG. 5 is an example feedback loop for updating QA pair answers by theresponse process of FIG. 1 according to one or more exampleimplementations of the disclosure; and

FIG. 6 is an example feedback loop for updating QA pair answers by theresponse process of FIG. 1 according to one or more exampleimplementations of the disclosure.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

System Overview:

As will be appreciated by one skilled in the art, aspects of the presentdisclosure may be embodied as a system, method or computer programproduct. Accordingly, aspects of the present disclosure may take theform of an entirely hardware embodiment, an entirely software embodiment(including firmware, resident software, micro-code, etc.) or anembodiment combining software and hardware aspects that may allgenerally be referred to herein as a “circuit,” “module” or “system.”Furthermore, aspects of the present disclosure may take the form of acomputer program product embodied in one or more computer readablemedium(s) having computer readable program code embodied thereon.

Any combination of one or more computer readable medium(s) may beutilized. The computer readable medium may be a computer readable signalmedium or a computer readable storage medium. A computer readablestorage medium may be, for example, but not limited to, an electronic,magnetic, optical, electromagnetic, infrared, or semiconductor system,apparatus, or device, or any suitable combination of the foregoing. Morespecific examples (a non-exhaustive list) of the computer readablestorage medium would include the following: an electrical connectionhaving one or more wires, a portable computer diskette, a hard disk, arandom access memory (RAM), a read-only memory (ROM), an erasableprogrammable read-only memory (EPROM or Flash memory), an optical fiber,a portable compact disc read-only memory (CD-ROM), an optical storagedevice, a magnetic storage device, or any suitable combination of theforegoing. In the context of this document, a computer readable storagemedium may be any tangible medium that can contain, or store a programfor use by or in connection with an instruction execution system,apparatus, or device.

A computer readable signal medium may include a propagated data signalwith computer readable program code embodied therein, for example, inbaseband or as part of a carrier wave. Such a propagated signal may takeany of a variety of forms, including, but not limited to,electro-magnetic, optical, or any suitable combination thereof. Acomputer readable signal medium may be any computer readable medium thatis not a computer readable storage medium and that can communicate,propagate, or transport a program for use by or in connection with aninstruction execution system, apparatus, or device.

Program code embodied on a computer readable medium may be transmittedusing any appropriate medium, including but not limited to wireless,wireline, optical fiber cable, RF, etc., or any suitable combination ofthe foregoing.

Computer program code for carrying out operations for aspects of thepresent disclosure may be written in any combination of one or moreprogramming languages, including an object oriented programming languagesuch as Smalltalk, C++ or the like and conventional proceduralprogramming languages, such as the “C” programming language or similarprogramming languages. The program code may execute entirely on theuser's computer, partly on the user's computer, as a stand-alonesoftware package, partly on the user's computer and partly on a remotecomputer or entirely on the remote computer or server. In the latterscenario, the remote computer may be connected to the user's computerthrough any type of network, including a local area network (LAN) or awide area network (WAN), or the connection may be made to an externalcomputer (for example, through the Internet using an Internet ServiceProvider).

Aspects of the present disclosure are described below with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems) and computer program products according to embodiments of thedisclosure. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer program instructions. These computer program instructions maybe provided to a processor of a general purpose computer, specialpurpose computer, or other programmable data processing apparatus toproduce a machine, such that the instructions, which execute via theprocessor of the computer or other programmable data processingapparatus, create means for implementing the functions/acts specified inthe flowchart and/or block diagram block or blocks.

These computer program instructions may also be stored in a computerreadable medium that can direct a computer, other programmable dataprocessing apparatus, or other devices to function in a particularmanner, such that the instructions stored in the computer readablemedium produce an article of manufacture including instructions whichimplement the function/act specified in the flowchart and/or blockdiagram block or blocks.

The computer program instructions may also be loaded onto a computer,other programmable data processing apparatus, or other devices to causea series of operational steps to be performed on the computer, otherprogrammable apparatus or other devices to produce a computerimplemented process such that the instructions which execute on thecomputer or other programmable apparatus provide processes forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods and computer program products according to variousembodiments of the present disclosure. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof code, which comprises one or more executable instructions forimplementing the specified logical function(s). It should also be notedthat, in some alternative implementations, the functions noted in theblock may occur out of the order noted in the figures. For example, twoblocks shown in succession may, in fact, be executed substantiallyconcurrently, or the blocks may sometimes be executed in the reverseorder, depending upon the functionality involved. It will also be notedthat each block of the block diagrams and/or flowchart illustration, andcombinations of blocks in the block diagrams and/or flowchartillustration, can be implemented by special purpose hardware-basedsystems that perform the specified functions or acts, or combinations ofspecial purpose hardware and computer instructions.

Referring now to FIG. 1, there is shown response process 10 that mayreside on and may be executed by a computer (e.g., computer 12), whichmay be connected to a network (e.g., network 14) (e.g., the internet ora local area network). Examples of computer 12 (and/or one or more ofthe client electronic devices noted below) may include, but are notlimited to, a personal computer(s), a laptop computer(s), mobilecomputing device(s), a server computer, a series of server computers, amainframe computer(s), or a computing cloud(s). Computer 12 may executean operating system, for example, but not limited to, Microsoft®Windows®; Mac® OS X®; Red Hat® Linux®, or a custom operating system.(Microsoft and Windows are registered trademarks of MicrosoftCorporation in the United States, other countries or both; Mac and OS Xare registered trademarks of Apple Inc. in the United States, othercountries or both; Red Hat is a registered trademark of Red HatCorporation in the United States, other countries or both; and Linux isa registered trademark of Linus Torvalds in the United States, othercountries or both).

As will be discussed below in greater detail, response process 10 mayreceive a first set of ground truth instances from a first source. Asecond set of ground truth instances may be received from a secondsource. The first and second sets of ground truth instances may beweighted differently based on a level of trust associated with each ofthe first and second sources. The weighted first and second sets ofground truth instances may be applied in a machine learning taskexecuted by a computer.

The instruction sets and subroutines of response process 10, which maybe stored on storage device 16 coupled to computer 12, may be executedby one or more processors (not shown) and one or more memoryarchitectures (not shown) included within computer 12. Storage device 16may include but is not limited to: a hard disk drive; a flash drive, atape drive; an optical drive; a RAID array; a random access memory(RAM); and a read-only memory (ROM).

Network 14 may be connected to one or more secondary networks (e.g.,network 18), examples of which may include but are not limited to: alocal area network; a wide area network; or an intranet, for example.

Computer 12 may include a data store, such as a database (e.g.,relational database, object-oriented database, triplestore database,etc.) and may be located within any suitable memory location, such asstorage device 16 coupled to computer 12. Any data described throughoutthe present disclosure may be stored in the data store. In someimplementations, computer 12 may utilize a database management systemsuch as, but not limited to, “My Structured Query Language” (MySQL®) inorder to provide multi-user access to one or more databases, such as theabove noted relational database. The data store may also be a customdatabase, such as, for example, a flat file database or an XML database.Any other form(s) of a data storage structure and/or organization mayalso be used. Response process 10 may be a component of the data store,a stand alone application that interfaces with the above noted datastore and/or an applet/application that is accessed via clientapplications 22, 24, 26, 28. The above noted data store may be, in wholeor in part, distributed in a cloud computing topology. In this way,computer 12 and storage device 16 may refer to multiple devices, whichmay also be distributed throughout the network.

Computer 12 may execute a Question Answering (QA) system application,such as (e.g., QA application 20), examples of which may include, butare not limited to, e.g., the IBM Watson™ application or other QAapplication, a search engine application, a natural language processing(NLP) application, or other application that allows for the answering ofquestions posed by a user by querying stored information, e.g., in adata store. Response process 10 and/or QA application 20 may be accessedvia client applications 22, 24, 26, 28. Response process 10 may be astand alone application, or may be anapplet/application/script/extension that may interact with and/or beexecuted within QA application 20, a component of QA application 20,and/or one or more of client applications 22, 24, 26, 28. QA application20 may be a stand alone application, or may be anapplet/application/script/extension that may interact with and/or beexecuted within response process 10, a component of response process 10,and/or one or more of client applications 22, 24, 26, 28. One or more ofclient applications 22, 24, 26, 28 may be a stand alone application, ormay be an apple/application/script/extension that may interact withand/or be executed within and/or be a component of response process 10and/or QA application 20. Examples of client applications 22, 24, 26, 28may include, but are not limited to, e.g., the IBM Watson™ applicationor other QA application, a search engine application, a natural languageprocessing (NLP) application, or other application that allows for theanswering of questions posed by a user by querying stored information,e.g., in a data store, a standard and/or mobile web browser, an emailclient application, a textual and/or a graphical user interface, acustomized web browser, a plugin, an Application Programming Interface(API), or a custom application. The instruction sets and subroutines ofclient applications 22, 24, 26, 28, which may be stored on storagedevices 30, 32, 34, 36, coupled to client electronic devices 38, 40, 42,44, may be executed by one or more processors (not shown) and one ormore memory architectures (not shown) incorporated into clientelectronic devices 38, 40, 42, 44.

Storage devices 30, 32, 34, 36, may include but are not limited to: harddisk drives; flash drives, tape drives; optical drives; RAID arrays;random access memories (RAM); and read-only memories (ROM). Examples ofclient electronic devices 38, 40, 42, 44 (and/or computer 12) mayinclude, but are not limited to, a personal computer (e.g., clientelectronic device 38), a laptop computer (e.g., client electronic device40), a smart/data-enabled, cellular phone (e.g., client electronicdevice 42), a notebook computer (e.g., client electronic device 44), atablet (not shown), a server (not shown), a television (not shown), asmart television (not shown), a media (e.g., video, photo, etc.)capturing device (not shown), and a dedicated network device (notshown). Client electronic devices 38, 40, 42, 44 may each execute anoperating system, examples of which may include but are not limited to,Android™, Apple® iOS®, Mac® OS X®; Red Hat® Linux®, or a customoperating system.

One or more of client applications 22, 24, 26, 28 may be configured toeffectuate some or all of the functionality of response process 10 (andvice versa). Accordingly, response process 10 may be a purelyserver-side application, a purely client-side application, or a hybridserver-side/client-side application that is cooperatively executed byone or more of client applications 22, 24, 26, 28 and/or responseprocess 10.

One or more of client applications 22, 24, 26, 28 may be configured toeffectuate some or all of the functionality of QA application 20 (andvice versa). Accordingly, QA application 20 may be a purely server-sideapplication, a purely client-side application, or a hybridserver-side/client-side application that is cooperatively executed byone or more of client applications 22, 24, 26, 28 and/or QA application20. As one or more of client applications 22, 24, 26, 28, responseprocess 10, and QA application 20, taken singly or in any combination,may effectuate some or all of the same functionality, any description ofeffectuating such functionality via one or more of client applications22, 24, 26, 28, response process 10, QA application 20, or combinationthereof, and any described interaction(s) between one or more of clientapplications 22, 24, 26, 28, response process 10, QA application 20, orcombination thereof to effectuate such functionality, should be taken asan example only and not to limit the scope of the disclosure.

Users 46, 48, 50, 52 may access computer 12 and response process 10(e.g., using one or more of client electronic devices 38, 40, 42, 44)directly through network 14 or through secondary network 18. Further,computer 12 may be connected to network 14 through secondary network 18,as illustrated with phantom link line 54. Response process 10 mayinclude one or more user interfaces, such as browsers and textual orgraphical user interfaces, through which users 46, 48, 50, 52 may accessresponse process 10.

The various client electronic devices may be directly or indirectlycoupled to network 14 (or network 18). For example, client electronicdevice 38 is shown directly coupled to network 14 via a hardwirednetwork connection. Further, client electronic device 44 is showndirectly coupled to network 18 via a hardwired network connection.Client electronic device 40 is shown wirelessly coupled to network 14via wireless communication channel 56 established between clientelectronic device 40 and wireless access point (i.e., WAP) 58, which isshown directly coupled to network 14. WAP 58 may be, for example, anIEEE 802.11a, 802.11b, 802.11g, Wi-Fi®, and/or Bluetooth™ device that iscapable of establishing wireless communication channel 56 between clientelectronic device 40 and WAP 58. Client electronic device 42 is shownwirelessly coupled to network 14 via wireless communication channel 60established between client electronic device 42 and cellularnetwork/bridge 62, which is shown directly coupled to network 14.

Some or all of the IEEE 802.11x specifications may use Ethernet protocoland carrier sense multiple access with collision avoidance (i.e.,CSMA/CA) for path sharing. The various 802.11x specifications may usephase-shift keying (i.e., PSK) modulation or complementary code keying(i.e., CCK) modulation, for example. Bluetooth™ is a telecommunicationsindustry specification that allows, e.g., mobile phones, computers,smart phones, and other electronic devices to be interconnected using ashort-range wireless connection. Other forms of interconnection (e.g.,Near Field Communication (NFC)) may also be used.

Referring also to FIG. 2, there is shown a diagrammatic view of clientelectronic device 38. While client electronic device 38 is shown in thisfigure, this is for illustrative purposes only and is not intended to bea limitation of this disclosure, as other configurations are possible.For example, any computing device capable of executing, in whole or inpart, response process 10 may be substituted for client electronicdevice 38 within FIG. 2, examples of which may include but are notlimited to computer 12 and/or client electronic devices 40, 42, 44.

Client electronic device 38 may include a processor and/ormicroprocessor (e.g., microprocessor 200) configured to, e.g., processdata and execute the above-noted code/instruction sets and subroutines.Microprocessor 200 may be coupled via a storage adaptor (not shown) tothe above-noted storage device(s) (e.g., storage device 30). An I/Ocontroller (e.g., I/O controller 202) may be configured to couplemicroprocessor 200 with various devices, such as keyboard 206,pointing/selecting device (e.g., mouse 208), custom device (e.g., device215), USB ports (not shown), and printer ports (not shown). A displayadaptor (e.g., display adaptor 210) may be configured to couple display212 (e.g., CRT or LCD monitor(s)) with microprocessor 200, while networkcontroller/adaptor 214 (e.g., an Ethernet adaptor) may be configured tocouple microprocessor 200 to the above-noted network 14 (e.g., theInternet or a local area network).

Question Answering (QA) systems, such as the IBM Watson™ system, mayinclude an application of advanced natural language processing,information retrieval, knowledge representation and reasoning, andmachine learning technologies to the field of open domain questionanswering. The IBM Watson™ system may be built on IBM's DeepQAtechnology (or other compatible technology) used for hypothesisgeneration, massive evidence gathering, analysis, and scoring. The IBMWatson™ system may take an input question, analyze it, decompose thequestion into constituent parts, generate one or more hypothesis basedon the decomposed question and results of a primary search of answersources, perform hypothesis and evidence scoring based on a retrieval ofevidence from evidence sources, perform synthesis of the one or morehypothesis, and based on trained models, perform a final merging andranking to output an answer to the input question along with aconfidence measure.

Some example QA systems may engage Subject Matter Experts (SMEs) tocreate the ground truth (candidate QA pairs) as part of QA systemtraining. In some QA systems, the collection of this ground truth may bedifficult and time consuming. For example, the process for this may havea unique set of questions that are given to each SME to create this set.In other example systems, a collaborative model may be used where eachSME is given the same questions and then through a group decision (e.g.,voting) come up with the most popular answers that are used to createthe set. Thus, the collection of this ground truth may be one of thelarger costs and efforts put forth when adapting to a new domain orcustomer.

The Response Process:

As discussed above and referring also at least to FIGS. 3-6, responseprocess 10 may receive 302 a first set of ground truth instances from afirst source. A second set of ground truth instances may be received 304by response process 10 from a second source. The first and second setsof ground truth instances may be weighted 306 differently by responseprocess 10 based on a level of trust associated with each of the firstand second sources. The weighted first and second sets of ground truthinstances may be applied 308 by response process 10 in a machinelearning task executed by a computer.

In some implementations, response process 10 may analyze a plurality ofground truth instances. Generally, a “ground truth instance” may bedescribed as a single input-output pair for which someone has judged theoutput to be valid given that input. As the present disclosure may beused in association with question answering, each input may be aquestion and each output may be an answer that someone has identified asa correct answer to that question. Thus, in the example, a single groundtruth instance may be a single QA pair, whereas multiple QA pairs may bereferred to as a set of ground truth instances or simply a ground truth.For example, response process 10 may be applied, e.g., at least duringthe ground truth creation, which may enable teaching or training QAapplication 20/response process 10. For example, response process 10 maycreate “levels” of ground truth. Each level may be indicative of theconfidence in the ground truth (e.g., the level of trust in the answerkey/source stating that the answer is correct and the degree to whichthe source indicates that the answer is correct). Each level may beorganized in the above-noted data store of computer 12. Response process10 may use these levels in the machine learning to help train QAapplication 20/response process 10, such that, e.g., response process 10may know that a ground truth instance (e.g., QA pair) at a higher levelhas some greater value (and thus confidence in the answer) than a QApair at a lower level. This may enable the collection of less groundtruth and the use of less subject matter expert (SME) time and effort tocurate the ground truth. Additionally, the graduated confidence scoresderived from the different levels of ground truth may be used to tailorsystem interaction for answers that may be less than perfect (i.e., notat the top or “gold” level).

In some implementations, for a particular domain and/or customer, theremay be a plurality of ground truth instances. In some implementations,response process 10 may receive 302 a first set of ground truthinstances from a first source. For example, for a first answerassociated with the plurality of ground truth instances (e.g., the firstset of ground truth instances), a first source validating the firstanswer may be determined by response process 10. For instance, assumefor example purposes only that there may be multiple sources that may beable to validate a particular answer in a QA pair instance. In theexample, assume the potential sources include, e.g., a subject matterexpert (SME), a developer of QA application 20, a threshold number ofcrowdsource users, etc. Each potential source may validate a particularanswer using traditional techniques, e.g., via a computing device suchas client electronic device 38. It will be appreciated that variousother sources and combinations thereof may also be used to validate aparticular answer without departing from the scope of the disclosure.

Continuing with the above example, further assume that the first answermay be associated by response process 10 with a first hierarchicalconfidence level based upon, at least in part, the first sourcevalidating the first answer. In the example, the level of trustassociated with the first set of ground truth instances may beindicative of validation of the first set of ground truth instances by asubject matter expert. For instance, associating the first answer withthe first hierarchical confidence level may be indicative of validationof the first answer by a subject matter expert. In some implementations,a second set of ground truth instances may be received 304 by responseprocess 10 from a second source. For instance, for a second answerassociated with the plurality of ground truth instances (e.g., thesecond set of ground truth instances), a second source validating thesecond answer may be determined by response process 10. In the example,the level of trust associated with the second set of ground truthinstances may be indicative of validation of the second set of groundtruth instances by a QA system developer. For instance, associating thesecond answer with the second hierarchical confidence level may beindicative of validation of the second answer by QA system developer.For instance, assume for example purposes only that the second answermay be selected by QA application 20, and validated (e.g., asacceptable) by a developer of QA application 20, but not validated by anSME. Continuing with the above example, the second answer may beassociated by response process 10 with a second hierarchical confidencelevel based upon, at least in part, the second source validating thesecond answer.

As will be discussed in greater detail below, the first and second setsof ground truth instances may be weighted 306 differently based on alevel of trust associated with each of the first and second sources. Inthe example, the first answer associated with the first hierarchicalconfidence level may be indicative of a higher confidence level in thefirst source than the second source. In some implementations, the firstanswer associated with the first hierarchical confidence level may bepreferred more than the second answer associated with the secondhierarchical confidence level. For instance, assume for example purposesonly that the first answer and the second answer are answers directedtowards the same question. Further assume that there is more confidencein an answer validated by a SME than an answer validated by a developerof QA application 20. Thus, in the example, since the first answer wasdetermined to be validated by a more trusted source (e.g., the SME), themore trusted first answer may be associated with the first hierarchicalconfidence level; and since the second answer was determined to bevalidated by a less trusted source (e.g., a developer of QA application20 and not validated by the SME), the less trusted second answer may beassociated with the second hierarchical confidence level. Therefore, inthe example, there may be a higher confidence in the first source (andtherefore the first answer associated with the first hierarchicalconfidence level) than in the second source (and therefore the secondanswer associated with the second hierarchical confidence level).

As such, in the example, there may be a ranking that returns the firstanswer over the second answer (e.g., in response to a query involvingthe associated question for the first and second answer). It will beappreciated that various techniques to return answers may be usedwithout departing from the scope of the disclosure. For example, bothanswers may be returned and may be ranked according to the hierarchicalconfidence level associated with the respective answer. For example, ifboth answers are returned, the first answer associated with the firsthierarchical confidence level may be returned and ranked higher than thesecond answer associated with the second hierarchical confidence level.In some implementations, only the answer associated with the highestavailable hierarchical confidence level may be returned. For instance,in the example, only the first answer would be returned since it isassociated with a higher hierarchical confidence level than the secondanswer. As such, any specific technique to return answers should betaken as example only and not to otherwise limit the scope of thedisclosure.

Continuing with the above example, in some implementations, variousother hierarchical confidence levels may be included. For example, athird set of ground truth instances may be received 310 from a thirdsource, and, as will be discussed further below, the third set of groundtruth instances may be weighted 312 differently than the first andsecond sets of ground truth instances based on a level of trustassociated with each of the first, second, and third sources. Forinstance, for a third answer associated with the plurality of groundtruth instances, a third source validating the third answer may bedetermined by response process 10. The third answer may be associated byresponse process 10 with a third hierarchical confidence level basedupon, at least in part, the third source validating the third answer,wherein the second answer associated with the second hierarchicalconfidence level may be preferred more than the third answer associatedwith the third hierarchical confidence level.

For instance, assume for example purposes only that the third answer maybe selected by QA application 20, and validated (e.g., as acceptable) byat least, e.g., three crowdsourcing users, but not validated by adeveloper of QA application 20 or a SME. For example, crowdsourcing maybe accomplished by, e.g., a service provided where users may sign up totake on problems and respond with their opinions to train QA application20. For instance, in some implementations, the crowdsource users may seethe user interface and the responses of QA application 20, and may markthem as “good” or “bad” for the validation. In the example, the level oftrust associated with the third set of ground truth instances may beindicative of validation of the third set of ground truth instances by athreshold number of crowdsource users. For instance, associating thethird answer with the third hierarchical confidence level may beindicative of validation of the third answer by a threshold number ofcrowdsource users. In the example, when a threshold number ofcrowdsource users (e.g., at least three) validate (e.g., via responseprocess 10) the third answer as “good”, response process 10 mayassociate the third answer with the third hierarchical confidence level.In some implementations, the crowdsource users may not necessarily bedirectly associated with the particular domain for the question beingasked. For instance, the crowdsource users may not be a developer of QAapplication 20 or a customer/SME associated with the particular domainfor the question being validated by the crowdsource users.

Assume for example purposes only that the first answer, the secondanswer, and the third answer are answers directed towards the samequestion. Further assume that there is more confidence in an answervalidated by a SME than an answer validated by a developer of QAapplication 20, and more confidence in an answer validated by adeveloper of QA application 20 than an answer validated by crowdsourceusers. Thus, in the example, since the first answer was determined to bevalidated by a more trusted source (e.g., the SME), the more trustedfirst answer may be associated with the first hierarchical confidencelevel; since the second answer was determined to be validated by a lesstrusted source (e.g., a developer of QA application 20 and not validatedby the SME), the less trusted second answer may be associated with thesecond hierarchical confidence level; and since the third answer wasdetermined to be validated by an even lesser trusted source (e.g., athreshold number of crowdsource users and not by a developer of QAapplication 20 and/or the SME), the lesser trusted third answer may beassociated with the third hierarchical confidence level. Therefore, inthe example, there may be a higher confidence in the first source (andtherefore the first answer associated with the first hierarchicalconfidence level) than in the second source (and therefore the secondanswer associated with the second hierarchical confidence level) and/orthe third source (and therefore the third answer associated with thethird hierarchical confidence level). In some implementations, responseprocess 10 may be trained such that it prefers a first hierarchicalconfidence level match over second hierarchical confidence level orthird hierarchical confidence level matches, but may still use thesecond hierarchical confidence level or even the third hierarchicalconfidence level matches as a fall-back strategy.

As noted above, the first and second sets of ground truth instances maybe weighted 306 differently based on a level of trust associated witheach of the first and second sources. In some implementations, theweighted 306 first and second sets of ground truth instances may beapplied 308 in a machine learning task executed by a computer. Forinstance, for statistical machine learning, response process 10 mayupweight the first hierarchical confidence level instances more than thesecond and third hierarchical confidence levels. For instance, applying308 the weighted first and second sets of ground truth instances in themachine learning task may include adjusting 309 a loss function for atleast one of the first and second sets of ground truth instances basedupon, at least in part, the level of trust associated with each of thefirst and second sources. In some implementations, the loss function forthe first set of ground truth instances may be adjusted 309 more thanthe second set of ground truth instances. For example, a loss functionmay be adjusted 309 for the first answer and the second answer basedupon, at least in part, the first source validating the first answer andthe second source validating the second answer, wherein the lossfunction for the first answer validated by the first source may beadjusted 309 more than the second answer validated by the second source.For instance, in general, statistical machine learning algorithms (whichmay be included as part of response process 10) may be designed tominimize “loss” (or equivalently, maximize “gain” where “gain” may bedefined as 0-loss) on some training data (e.g., the set of ground truthinstances). In the example, response process 10 may revise or adjust 309the “loss” function for the learning to provide more loss when the model(executed by response process 10) fails to match the outcome on a morehighly trusted ground truth answer (e.g., the first hierarchicalconfidence level) than it does when the model fails to match the outcomeon a less trusted confidence ground truth answer but still provide someloss even for the lower levels of trust (e.g., the second and thirdhierarchical confidence levels). This example approach may providebetter results than learning over just your highly trusted ground truthinstances, at least because response process 10 may learn from a largerquantity of data. Response process 10 may provide better results thanlearning over all of the ground truth instances without differentiatingamong them, at least because the model may be more highly influenced bythe more trusted instances and may be only moderately influenced by theless trusted ones.

In some implementations, applying 308 the weighted first and second setsof ground truth instances in the machine learning task may include atleast one of a mean-squared error and duplication of instances for thefirst set of ground truth instances more than the second set of groundtruth instances. For instance, as another example of adjusting 309 aloss function, a mean-squared-error may be used by response process 10,in which the loss for a training set may be the mean across allinstances in the set of the square of the error. In this context (e.g.,question-answer pairs), with ground truth instances marked as right orwrong, response process 10 may define “error” to be the confidence inthe answer if that answer is wrong and one minus the confidence in theanswer if that answer is right. When a learning algorithm (such as anexample learning algorithm used by response process 10) finds a modelthat minimizes the mean-squared error for a training set, that model mayproduce higher confidences for right answers (and thus associated with ahigher hierarchical confidence level) and lower confidences on wronganswers (and thus associated with a lower hierarchical confidence levelrespectively) than competing models. In some implementations, an exampletechnique for response process 10 to adjust 309 the mean-squared-errorloss function to reflect the level of trust in the source of a groundtruth instance may be to multiply the loss for a single instance by adistinct numerical constant for each source. For example, responseprocess 10 may multiply the error by 0.2 for instances that came frommildly trusted sources (e.g., crowdsourced users), by 0.6 for instancesthat came from moderately trusted sources (e.g., developers of QAapplication 20), and 1.0 for instances that came from highly trustedsources (e.g., SMEs). Response process 10 may then compute the mean ofthe squares of the errors multiplied by these constants instead of themean of the unmodified error values.

In some implementations, response process 10 may upweight the groundtruth instances by duplicating the more trusted instances one or moretimes. For instance, assume for example purposes only that responseprocess 10 has access to 300 highly trusted, 900 moderately trusted, and2,000 minimally trusted instances. In the example, response process 10may make 5 copies each of the 300 highly trusted instances and 2 copieseach of the 900 moderately trusted instances and put them all togetherinto one 5*300+2*900+2,000=5,300 instance set. Since each of the highlytrusted instances appears 5 times in the data set, they will have 5times as much influence on the total loss assigned to any model. As aresult, the model that minimizes loss on the training data (which may bethe one the statistical machine learning algorithm of response process10 is designed to find) will more thoroughly reflect experience from themost trusted data but will still partially reflect experience from theother data. As a result, a model that reflects the more trusted datamore thoroughly may be more effective, at least because the levels oftrust may be better correlated with the quality of an answer. In theexample, instead of having just “correct” and “incorrect” answers, whereevery “correct” answer may be manually validated by a human annotator(SME), response process 10 may take less time and effort than building acomparably sized ground truth from only highly trusted sources, and mayprovide better quality than a comparably sized ground truth that may beexclusively pulled from less expensive sources.

As such, in the example, there may be a ranking that returns the firstanswer over the second answer and/or the third answer (e.g., in responseto a query involving the associated question for the first, second, andthird answer). As noted above, it will be appreciated that varioustechniques to return answers may be used without departing from thescope of the disclosure. For example, all three answers may be returnedand may be ranked according to the hierarchical confidence levelassociated with the respective answer. For example, if all three answersare returned, the first answer associated with the first hierarchicalconfidence level may be returned and ranked higher than the secondanswer associated with the second hierarchical confidence level and thethird answer associated with the third hierarchical confidence level,where the second answer may be ranked higher than the third answer. Insome implementations, only the answer associated with the highestavailable hierarchical confidence level may be returned. For instance,in the example, only the first answer would be returned since it isassociated with a higher hierarchical confidence level than the secondand third answer. As such, any specific technique to return answersshould be taken as example only and not to otherwise limit the scope ofthe disclosure.

In some implementations, as part of a feedback loop, response process 10may analyze the correctness of the question, inspect the ground truthinstances that went into the answer being correct and have the abilityto “up-level” ground truth instances if they are contributing to correctanswers. For example, the levels of ground truth may be augmentedincrementally by response process 10 with cycles of semi-supervisedvalidation. As will be discussed in greater detail, silver instanceswith good agreement may be sent by response process 10 to additionaljudges for validation, and when an agreement threshold is reached thoseinstances may be sent by response process 10 to the SMEs for validation.As such, the number of instances moving through this flow may diminishwith time.

For instance, in some implementations, an answer in the second set ofground truth instances may be updated for association with the first setof ground truth instances in response to receiving validation of theanswer from a subject matter expert. For example, the second answer maybe updated 314 by response process 10 for association with the firsthierarchical confidence level in response to receiving validation of thesecond answer from a subject matter expert. Similarly, the third answermay be updated by response process 10 for association with the second orfirst hierarchical confidence level in response to receiving validationof the respective trusted source associated with the respectivehierarchical confidence level.

For example, and referring at least to FIGS. 4-6, assume for examplepurposes only that three levels exist for the hierarchical confidencelevels. In the example, answers selected and/or validated by SMEs may bethe most trusted (e.g., “gold”) confidence level, and thus may beassociated with the gold hierarchical confidence level. Further in theexample, answers validated by developers of QA application 20 may be thesecond most trusted (e.g., “silver”) confidence level, and thus may beassociated with the silver hierarchical confidence level. Further in theexample, answers validated by one or more of the above-noted crowdsourceusers may be the third most trusted (e.g., “bronze”) confidence level,and thus may be associated with the bronze hierarchical confidencelevel.

In the example, assume that the third answer is associated with QA pair400, and that the second answer is associated with QA pair 402. In theexample, further assume that response process 10 has determined that atleast one crowdsource user has validated the answer for QA pair 400, andtherefore may be associated with the bronze confidence level. In theexample, further assume that response process 10 has determined that atleast one developer for QA application 20 has validated the answer forQA pair 402, and therefore may be associated with the silver confidencelevel. In some implementations, response process 10 may determine that athreshold number (e.g., three) of crowdsource users has validated theanswer for QA pair 400. In response, the answer for QA pair 400 may beidentified and submitted to one or more developers for QA application 20to perform additional verification of the correctness of the answer. Inthe example, if a threshold number (e.g., one) of developers of QAapplication 20 validate the answer for QA pair 400, response process 10may update its associated confidence level from bronze to silver (asshown in FIG. 5). In some implementations, response process 10 may usetechniques such as, e.g., the minimax entropy principle to improve thequality of so-called “noisy labels” from crowdsource users ofnon-experts to select the “best” answers from the bronze level.

In some implementations, response process 10 may determine that athreshold number (e.g., one) of developers for QA application 20 hasvalidated the answer for QA pair 402. In response, the answer for QApair 402 may be identified and submitted to one or more SMEs to performadditional verification of the correctness of the answer. In theexample, if a threshold number (e.g., one) of SMEs validate the answerfor QA pair 402, response process 10 may update 314 its associatedconfidence level from silver to Gold (as shown in FIGS. 5 and 6).Conversely, in the example, if the threshold number of SMEs do notvalidate the answer for QA pair 402, response process 10 may maintainthe answer for QA pair 402 in the silver level.

In some implementations, and referring at least to FIG. 5, responseprocess 10 may determine that a threshold number (e.g., one) ofdevelopers for QA application 20 has validated the answer for QA pair400. In response, the answer for QA pair 400 may be identified andsubmitted to one or more SMEs to perform additional verification of thecorrectness of the answer. In the example, if a threshold number (e.g.,one) of SMEs validate the answer for QA pair 400, response process 10may update its associated confidence level from silver to Gold (as shownin FIG. 6). Conversely, in the example, if the threshold number of SMEsdo not validate the answer for QA pair 400, response process 10 maymaintain the answer for QA pair 400 in the silver level.

In some implementations, the above-noted thresholds for the number ofcrowdsource users, developers of QA application 20 and/or SMEs may beset (e.g., via response process 10) for a given tolerance window forcustomer involvement. For instance, a user interface (not shown)associated with response process 10 may enable a user (e.g., thecustomer SME) to change the number of respective sources (e.g.,crowdsource users, QA application 20 developers, SMEs) that may berequired to validate a particular answer before graduating the answer tothe next hierarchical level of trust. Thus, in the example, responseprocess 10 may enable the collection of less ground truth and the use ofless subject matter expert (SME) time and effort to curate the groundtruth.

It will be appreciated that while three hierarchical confidence levelsare described, more or less levels may be used without departing fromthe scope of the disclosure. As such, the use of three hierarchicalconfidence levels should be taken as example only and not to limit thescope of the disclosure. It will also be appreciated that any othersources may be used without departing from the scope of the disclosure.As such, the use of crowdsource users, application developers and SMEsas sources should be taken as example only and not to limit the scope ofthe disclosure. It will also be appreciated that various sources mayprovide validations with higher confidence levels without departing fromthe scope of the disclosure. For example, the crowdsource users mayprovide validation for answers that provides a higher confidence levelthan the SMEs (e.g., in more general domains). As another example, eachhierarchical level may include varying combinations of each source. Assuch, the example organization and implementation of the threehierarchical confidence levels should be taken as example only and notto limit the scope of the disclosure.

The terminology used herein is for the purpose of describing particularimplementations only and is not intended to be limiting of thedisclosure. As used herein, the singular forms “a”, “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps (notnecessarily in a particular order), operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, integers, steps (not necessarily in a particular order),operations, elements, components, and/or groups thereof.

The corresponding structures, materials, acts, and equivalents of allmeans or step plus function elements that may be in the claims below areintended to include any structure, material, or act for performing thefunction in combination with other claimed elements as specificallyclaimed. The description of the present disclosure has been presentedfor purposes of illustration and description, but is not intended to beexhaustive or limited to the disclosure in the form disclosed. Manymodifications, variations, substitutions, and any combinations thereofwill be apparent to those of ordinary skill in the art without departingfrom the scope and spirit of the disclosure. The implementation(s) werechosen and described in order to best explain the principles of thedisclosure and the practical application, and to enable others ofordinary skill in the art to understand the disclosure for variousimplementation(s) with various modifications and/or any combinations ofimplementation(s) as are suited to the particular use contemplated.

Having thus described the disclosure of the present application indetail and by reference to implementation(s) thereof, it will beapparent that modifications, variations, and any combinations ofimplementation(s) (including any modifications, variations,substitutions, and combinations thereof) are possible without departingfrom the scope of the disclosure defined in the appended claims.

What is claimed is:
 1. A computer-implemented method comprising:receiving, by a computing device, a first set of ground truth instancesfrom a first source; receiving a second set of ground truth instancesfrom a second source; weighting the first and second sets of groundtruth instances differently based on a level of trust associated witheach of the first and second sources; and applying the weighted firstand second sets of ground truth instances in a machine learning taskexecuted by a computer, wherein applying the weighted first and secondsets of ground truth instances in the machine learning task includesadjusting a loss function for at least one of the first and second setsof ground truth instances based upon, at least in part, the level oftrust associated with each of the first and second sources, and at leastone of a mean squared error and duplication of instances for the firstset of ground truth instances over that of the second set of groundtruth instances, wherein the first set of ground truth instances aremore trusted than the second set of ground truth instances, and whereina model is created by the duplication of instances for the first set ofground truth instances in a model data set to create a more effectivemodel by more thoroughly reflecting more trusted data.
 2. Thecomputer-implemented method of claim 1 further comprising: receiving athird set of ground truth instances from a third source; and weightingthe third set of ground truth instances differently than the first andsecond sets of ground truth instances based on a level of trustassociated with each of the first, second, and third sources, whereinthe weighted first, second, and third sets of ground truth instances areapplied in the machine learning task.
 3. The computer-implemented methodof claim 1 wherein the level of trust associated with the first set ofground truth instances is indicative of validation of the first set ofground truth instances by a subject matter expert.
 4. Thecomputer-implemented method of claim 1 wherein the level of trustassociated with the second set of ground truth instances is indicativeof validation of the second set of ground truth instances by QA systemdeveloper, and wherein the level of trust associated with the third setof ground truth instances is indicative of validation of the third setof ground truth instances by a threshold number of crowdsource users. 5.The computer-implemented method of claim 1 further comprising updatingan answer in the second set of ground truth instances for associationwith the first set of ground truth instances in response to receivingvalidation of the answer from a subject matter expert.